Media transport

ABSTRACT

A media transport includes a feed roller to be rotated in a first direction, and an input/output roller to be rotated in the first direction to direct media into a media path with rotation of the feed roller in the first direction, where the feed roller is to be rotated in a second direction opposite the first direction to advance the media within the media path and, with the rotation of the feed roller in the second direction, the input/output roller is to be temporarily decoupled from rotation with the feed roller.

BACKGROUND

A printer may include a media transport assembly to move and/or route print media through the printer, and a print engine to print on the print media. To route the print media through the printer, the media transport assembly may include a variety of guides, rollers, wheels, etc.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1, 2 are schematic views illustrating an example of a media transport assembly.

FIG. 3 is a perspective view illustrating an example of a media transport assembly.

FIGS. 4A, 4B are exploded perspective views illustrating an example of a transmission of the media transport assembly of FIG. 3 .

FIGS. 5A, 5B, 5C, 5D are schematic cross-sectional views illustrating an example of stages of the transmission of FIGS. 4A, 4B of the media transport assembly of FIG. 3 .

FIG. 6 is a flow diagram illustrating an example of a media transport method.

FIG. 7 is a block diagram illustrating an example of an inkjet printing system including an example of a media transport assembly.

DETAILED DESCRIPTION

In the following detailed description, reference is made to the accompanying drawings which form a part hereof, and in which is shown by way of illustration specific examples in which the disclosure may be practiced. It is to be understood that other examples may be utilized and structural or logical changes may be made without departing from the scope of the present disclosure.

As illustrated in the example of FIGS. 1, 2 , the present disclosure provides a media transport assembly 100. In one implementation, as illustrated in the example of FIG. 1 , media transport assembly 100 includes a feed roller 140 to be rotated in a first direction D1, and an input/output roller 160 to be rotated in first direction D1 with rotation of feed roller 140 in first direction D1 (such that, in examples, input/output roller 160 is coupled with rotation of feed roller 140, as schematically represented by 101 in FIG. 1 ). As such, input/output roller 160 is to direct media 110 into a media path 120. In one implementation, as illustrated in the example of FIG. 2 , feed roller 140 is to be rotated in a second direction D2 opposite first direction D1 to advance media 110 within media path 120, such that, with rotation of feed roller 140 in second direction D2, input/output roller 160 is to be temporarily decoupled from rotation with feed roller 140 (as schematically represented by 102 in FIG. 2 ).

With a media transport assembly and a media transport method, as disclosed herein, rotation of an input/output roller, such as, for example, input/output roller 160, may be coupled with rotation of a feed roller, such as, for example, feed roller 140, when the feed roller is rotated in one direction, and temporarily decoupled from rotation with the feed roller when the feed roller is rotated in an opposite direction. As such, a common (single) motor may be used for actuation or operation of both the input/output roller and the feed roller. Accordingly, use of a common (single) motor may provide cost savings as compared to other systems which rely on multiple motors.

In addition, coupling rotation of an input/output roller with rotation of a feed roller, such as, for example, coupling rotation of input/output roller 160 with rotation of feed roller 140, as disclosed herein, and temporarily decoupling rotation of the input/output roller from rotation with the feed roller, such as, for example, temporarily decoupling rotation of input/output roller 160 from rotation with feed roller 140, as disclosed herein, enables support of media within a media path by the input/output roller when or as the media is advanced by the feed roller. Thus, the input/output roller may be used to both direct media into the media path and support media within media the path such that the media path may be shorter than the longest length of supported media. Accordingly, temporarily decoupling rotation of the input/output roller from rotation with the feed roller may allow for a shorter media path and, therefore, smaller printer footprint as compared to other systems which rely on a media path longer than the longest length of supported media to avoid media jams between feed and input/output rollers when the media is in contact with both the feed and input/output rollers and the feed and input/output rollers are both rotated in the same direction.

FIG. 3 illustrates an example of a media transport assembly 200, as an example of media transport assembly 100. In one implementation, media transport assembly 200 includes a media path 202, an input/output shaft 210, an input/output roller 212 (see, for example, FIG. 5A) on input shaft 210, a feed shaft 220, a feed roller 222 on feed shaft 220, a drive motor 204, and a transmission 230 to transfer rotational power from drive motor 204 to feed roller 222 (via feed shaft 220) and input/output roller 212 (see, for example, FIG. 5A) (via input/output shaft 210). In examples, transmission 230 synchronizes (and de-synchronizes) rotation of input/output shaft 210 and feed shaft 220 (and, therefore, rotation of input/output roller 212 and feed roller 222) to route media through media path 202. As such, media transport assembly 200 routes media to and through a print zone for printing on the media by a print engine.

In examples, transmission 230 transmits rotational power of drive motor 204 to feed shaft 220 and input/output shaft 210. In one implementation, transmission 230 includes a drive gear 232 (see, for example, FIG. 4B) coupled with or secured to feed shaft 220 to drive feed roller 222, a drive gear 234 coupled with or secured to input/output shaft 210 to drive input/output roller 212, and a delay clutch 240 in a power transmission path between drive gear 232 and drive gear 234 (FIG. 4B).

In examples, delay clutch 240 couples rotation of input/output shaft 210 with rotation of feed shaft 220 (and, therefore, couples rotation of input/output roller 212 with rotation of feed roller 222) and temporarily decouples rotation of input/output shaft 210 from rotation of feed shaft 220 (and, therefore, temporarily decouples rotation of input/output roller 212 from rotation of feed roller 222). In one implementation, delay clutch 240 couples and temporarily decouples rotation of input/output shaft 210 with rotation of feed shaft 220 (and, therefore, rotation of input/output roller 212 with rotation of feed roller 222) based on a direction of rotation, including, more specifically, a direction of rotation of drive gear 232 (as driving feed shaft 220 and feed roller 222). As further described herein, FIGS. 4A, 4B illustrate an example of delay clutch 240.

In one implementation, transmission 230 includes an intermediate gear 236 between drive gear 232 and delay clutch 240 to transfer rotational power from drive gear 232 to delay clutch 240, and an intermediate gear 238 between delay clutch 240 and drive gear 234 to transfer rotational power from delay clutch 240 to drive gear 234. As such, in examples, rotational power of motor 204 is transmitted to feed shaft 220 via drive gear 232, and transmitted to input/output shaft 210 via drive gear 232, intermediate gear 236, delay clutch 240, intermediate gear 238, and drive gear 234. Although intermediate gear 236 and intermediate gear 238 are each illustrated as being a single gear, intermediate gear 236 or intermediate gear 238 may each include more than one gear.

FIGS. 4A, 4B illustrate an example of transmission 230 with delay clutch 240. In one implementation, delay clutch 240 includes a first delay gear 242, a second delay gear 244, and a delay disc 246 interposed between first delay gear 242 and second delay gear 244. As such, based on a direction of rotation of first delay gear 242, interaction of first delay gear 242 with delay disc 246 and interaction of delay disc 246 with second delay gear 244 couples rotation of second delay gear 244 with rotation of first delay gear 242, or temporarily decouples rotation of second delay gear 244 from rotation with first delay gear 242, as further disclosed herein.

In examples, first delay gear 242, second delay gear 244, and delay disc 246 include respective engagement features to couple or transfer rotation of first delay gear 242 to second delay gear 244 via delay disc 246 and temporarily decouple rotation of second delay gear 244 from rotation of first delay gear 242 based on a direction of rotation of first delay gear 242. In one implementation, first delay gear 242 includes a protrusion or raised portion on a side facing delay disc 246, such as, for example, radial arm or radial rib 243 on side 2421, second delay gear 244 includes a protrusion or raised portion on a side facing delay disc 246, such as, for example, radial arm or radial rib 245 on side 2441, and delay disc 246 includes a protrusion or raised portion on a side facing first delay gear 242, such as, for example, arcuate rib 247 on side 2461 and a protrusion or raised portion on a side facing second delay gear 244, such as, for example, arcuate rib 248 on side 2462. As such, rotation of first delay gear 242 is transferred to second delay gear 244 via delay disc 246 based on interaction or contact between radial rib 243 and arcuate rib 247 and interaction or contact between radial rib 245 and arcuate rib 248.

For example, with rotation of drive gear 232 in a first direction D1 and, therefore, rotation of first delay gear 242 in first direction D1, radial rib 243 of first delay gear 242 engages or contacts arcuate rib 247 of delay disc 246 and arcuate rib 248 of delay disc 246 engages or contacts radial rib 245 of second delay gear 244 such that rotation of first delay gear 242 is transferred to second delay gear 244 via delay disc 246. Thus, delay disc 246 and second delay gear 244 both rotate in first direction D1 with first delay gear 242 such that drive gear 234 rotates in first direction D1 with drive gear 232 (via intermediate gear 236, delay clutch 240, and intermediate gear 238). Accordingly, rotation of input/output shaft 210 and, therefore, rotation of input/output roller 212, is coupled with rotation of feed shaft 220 and, therefore, rotation of feed roller 222.

With rotation of drive gear 232 in a second direction D2, opposite first direction D1, and, therefore, rotation of first delay gear 242 in second direction D2, however, radial rib 243 of first delay gear 242 is disengaged from or out of contact with arcuate rib 247 of delay disc 246 for an amount of rotation of first delay gear 242 (for example, a number of degrees of rotation of first delay gear 242). As such, first delay gear 242 rotates in second direction D2 without corresponding rotation of second delay gear 244. Second delay gear 244, therefore, is disengaged from rotation with first delay gear 242 such that second delay gear 244 may remain stationary as first delay gear 242 rotates for an amount of rotation (for example, a number of degrees of rotation). Thus, delay clutch 240 temporarily decouples rotation of drive gear 234 from rotation of drive gear 232. Accordingly, rotation of input/output shaft 210 and, therefore, rotation of input/output roller 212, is temporarily decoupled from rotation of feed shaft 220 and, therefore, rotation of feed roller 222 based on a direction and amount of rotation.

With further rotation of drive gear 232 in second direction D2 and, therefore, further rotation of first delay gear 242 in second direction D2, radial rib 243 of first delay gear 242 engages or contacts arcuate rib 247 of delay disc 246 and arcuate rib 248 of delay disc 246 engages or contacts radial rib 245 of second delay gear 244 such that rotation of first delay gear 242 is transferred to second delay gear 244 via delay disc 246. Thus, delay disc 246 and second delay gear 244 both rotate in second direction D2 with first delay gear 242 such that drive gear 234 rotates in second direction D2 with drive gear 232. Accordingly, rotation of input/output shaft 210 and, therefore, rotation of input/output roller 212, is coupled (re-coupled) with rotation of feed shaft 220 and, therefore, rotation of feed roller 222.

FIGS. 5A, 5B, 5C, 5D illustrate examples of different stages of transmission 230 of media transport assembly 200 in routing or transporting media through media path 202. In examples, media path 202 is a duplex media path such that media is first routed through media path 202 to print on a first side of the media, and then rerouted through media path 202 to print on a second side of the media opposite the first side. In the examples of FIGS. 5A, 5B, 5C, 5D, transmission 230 is illustrated as being displaced from media transport assembly 200 so as to avoid obstruction of media path 202, input/output shaft 210, input/output roller 212, feed shaft 220, and feed roller 222.

FIG. 5A illustrates an example of transmission 230 in an initial (for example, first) stage 501. In stage 501, drive gear 232 (via motor 204, FIG. 3 ) is rotated in direction D1 (counter-clockwise in the illustrated example) such that rotation of drive gear 232 is transmitted to drive gear 234 via intermediate gear 236, delay clutch 240, and intermediate gear 238, as indicated by power transmission path 251. More specifically, in examples, delay clutch 240 is engaged such that first delay gear 242 (FIGS. 4A, 4B) and second delay gear 244 (FIGS. 4A, 4B) both rotate in direction D1 (as represented by arrows D1-1, D1-2) to transmit rotational power to drive gear 234. As such, rotation of drive gear 232 in direction D1 results in rotation of drive gear 234 in direction D1 such that input/output shaft 210 and, therefore, input/output roller 212, rotate in direction D1. Thus, rotation of input/output roller 212 in direction D1 draws media 206 into media path 202 in direction D1 such that an end or leading portion 207 of media 206 is at input/output roller 212. For example, end or leading portion 207 of media 206 is at or in a nip formed by and between input/output roller 212 and an opposing roller 213 (such as, for example, a starweel or other element).

FIG. 5B illustrates an example of transmission 230 in a next (for example, second) stage 502. In stage 502, drive gear 232 and drive gear 234 (via intermediate gear 236, delay clutch 240, and intermediate gear 238, as indicated by power transmission path 251) continue to be rotated in direction D1. More specifically, in examples, delay clutch 240 continues to be engaged such that first delay gear 242 (FIGS. 4A, 4B) and second delay gear 244 (FIGS. 4A, 4B) both rotate in direction D1 (as represented by arrows D1-1, D1-2) to transmit rotational power to drive gear 234. As such, media 206 continues to be routed or transported through media path 202 by input/output roller 212. More specifically, media 206 is routed or transported through media path 202 such that end or leading portion 207 of media 206 is directed toward feed roller 222.

FIG. 5C illustrates an example of transmission 230 in a next (for example, third) stage 503. In stage 503, drive gear 232 is rotated in an opposite direction D2 (clockwise in the illustrated example) such that rotation of drive gear 232 in direction D2 results in rotation of feed shaft 220 and, therefore, feed roller 222 in direction D2. Thus, rotation of feed roller 222 in direction D2 continues to transport media 206 through media path 202 (for example, draw media 206 into and through media path 202) such that end or leading portion 207 of media 206 is at feed roller 222. For example, end or leading portion 207 of media 206 is at or in a nip formed by and between feed roller 222 and an opposing roller 223 (or other element).

In one implementation, a position of media 206 within media path 202 (for example, a position of end or leading portion 207 of media 206 within media path 202) is determined or sensed by a sensor 203 such that a change in direction of rotation of drive gear 232 (for example, from direction D1 to direction D2) is triggered or initiated based on end or leading portion 207 of media 206 passing sensor 203 buy a defined amount or distance.

In stage 503, with delay clutch 240 in transmission 230 between drive gear 232 and drive gear 234, rotation of drive gear 234 (and, therefore, rotation of input/output shaft 210 and input/output roller 212) is temporarily decoupled from rotation of drive gear 232, as indicated by power transmission path 252. More specifically, in examples, delay clutch 240 is disengaged such that first delay gear 242 (FIGS. 4A, 4B) rotates (as represented by arrow D2-1) relative to second delay gear 244 (FIGS. 4A, 4B). As such, drive gear 234 (and, therefore, input/output shaft 210 and input/output roller 212) is in a neutral state (as represented by double arrow N) such that drive gear 234 (and, therefore, input/output shaft 210 and input/output roller 212) is free to rotate in either direction irrespective of the direction of rotation of drive gear 232 (and, therefore, irrespective of the direction of rotation of feed shaft 220 and feed roller 222). For example, drive gear 234 is free to rotate in direction D1 (counter-clockwise in the illustrated example) as drive gear 232 (and, therefore, feed shaft 220 and feed roller 222) is rotated in direction D2 (clockwise in the illustrated example). Thus, end or trailing portion 208 of media 206 may be supported within media path 202 by input/output roller 212 as media is advanced or fed through media path by feed roller 222. More specifically, end or trailing portion 208 of media 206 may be supported by input/output roller 212 and input/output roller 212 is free to rotate in direction D1, as leading portion 207 of media 206 is advanced or fed by feed roller 222 in direction D2 (opposite direction D1).

FIG. 5D illustrates an example of transmission 230 in a next (for example, fourth) stage 504. In stage 504, drive gear 232 continues to be rotated in direction D2 (clockwise in the illustrated example) such that feed shaft 220 and, therefore, feed roller 222 continues to transport media 206 through media path 202. More specifically, media 206 is advanced or fed through media path 202 to and through a print zone 262 for printing on media 206 by a print engine 264.

With the continued rotation of drive gear 232 in direction D2, the delay (temporary decoupling) of delay clutch 240 is exhausted or used up such that drive gear 234 is re-engaged (via delay clutch 240 and intermediate gear 238) and rotated with drive gear 232 in direction D2. As such, rotation of drive gear 232 (via motor 204, FIG. 3 ) is transmitted to drive gear 234 via intermediate gear 236, delay clutch 240, and intermediate gear 238, as indicated by power transmission path 253. More specifically, in examples, delay clutch 240 is engaged such that first delay gear 242 (FIGS. 4A, 4B) and second delay gear 244 (FIGS. 4A, 4B) both rotate in direction D2 (as represented by arrows D2-1, D2-2) to transmit rotational power to drive gear 234. Accordingly, feed roller 222 and input/output roller 212 both rotate in direction D2.

In examples, with transport of media 206 through media path 202 by feed roller 222, end or leading portion 207 of media 206 and end or trailing portion 208 of media 206 may overlap in media path 202, as illustrated in the example of FIG. 5D. In one implementation, a flap or gate 260 is provided in an area of the media overlap to guide end or leading portion 207 of media 206 or end or trailing portion 208 of media 206. More specifically, based on a stage of operation of transmission 230, flap or gate 260 may be moved to guide media 206. For example, in stages 501, 502, 503, flap or gate 260 may be rotated downward to guide media 206 to a lower portion of media path 202 and feed roller 222, and, in stage 504, flap or gate 260 may be rotated upward to guide media 206 to an upper portion of media path 202 and input/output roller 212

FIG. 6 is a flow diagram illustrating an example of a method 600 of transporting media, such as media 206, as illustrated, for example, in FIGS. 5A, 5B, 5C, 5D.

At 602, method 600 includes rotating a feed roller in a first direction, such as rotating feed roller 222 in direction D1, as illustrated, for example, in FIGS. 5A, 5B.

At 604, method 600 includes coupling rotation of an input/output roller with the rotating the feed roller in the first direction to direct media into a media path, such as coupling rotation of input/output roller 212 with rotating of feed roller 222 in direction D1 to direct media 206 into media path 202, as illustrated, for example, in FIGS. 5A, 5B.

At 606, method 600 includes rotating the feed roller in a second direction opposite the first direction to advance the media within the media path, such as rotating feed roller 222 in direction D2 opposite direction D1 to advance media 206 within media path 202, as illustrated, for example, in FIGS. 5C, 5D. In examples, rotating the feed roller in a second direction opposite the first direction to advance the media within the media path, at 602, includes temporarily decoupling rotation of the input/output roller from the rotating with the feed roller, such as temporarily decoupling rotation of input/output roller 212 from rotating with feed roller 222, as illustrated, for example, in FIG. 5C.

With media transport assembly 200 and media transport method 600, as disclosed herein, rotation of input/output roller 212 may be coupled with rotation of feed roller 222 when feed roller 222 is rotated in one direction, and temporarily decoupled from rotation with feed roller 222 when feed roller 222 is rotated in an opposite direction. As such, a common (single) motor (e.g., motor 204, FIG. 3 ) may be used for actuation or operation of both input/output roller 212 and feed roller 222. In addition, coupling rotation of input/output roller 212 with rotation with feed roller 222 and temporarily decoupling rotation of input/output roller 212 from rotation with feed roller 222, as disclosed herein, enables support of media within media path 202 by input/output 212 roller as media is advanced by feed roller 222. Thus, input/output 212 roller may be used to both direct media into media path 202 and support media within media path 202.

In examples, media transport assembly 200 may be included in a printing system. FIG. 7 illustrates an example of an inkjet printing system 700 including a printhead assembly 702, as an example of a fluid ejection device, a fluid supply assembly 704, a mounting assembly 706, a media transport assembly 708, such as, for example, media transport assembly 200, an electronic controller 710, and a power supply 712 that provides power to electrical components of inkjet printing system 700. Printhead assembly 702 includes a printhead die 714, as an example of a fluid ejection die, that ejects drops of fluid through a plurality of orifices or nozzles 716 toward a print media 718 so as to print on print media 718.

Print media 718 can be any type of suitable sheet or roll material, such as paper, card stock, transparencies, Mylar, and the like, and may include rigid or semi-rigid material, such as cardboard or other panels. Nozzles 716 are typically arranged in columns or arrays such that properly sequenced ejection of fluid from nozzles 716 causes characters, symbols, and/or other graphics or images to be printed on print media 718 as printhead assembly 702 and print media 718 are moved relative to each other.

Fluid supply assembly 704 supplies fluid (e.g., ink or other liquid) to printhead assembly 702 such that fluid flows from fluid supply assembly 704 to printhead assembly 702. In one example, printhead assembly 702 and fluid supply assembly 704 are housed together in an inkjet cartridge or pen 720, as an example of a fluid ejection assembly. In another example, fluid supply assembly 704 is separate from printhead assembly 702 and supplies fluid to printhead assembly 702 through an interface connection, such as a supply tube.

Mounting assembly 706 positions printhead assembly 702 relative to media transport assembly 708, and media transport assembly 708 positions print media 718 relative to printhead assembly 702. Thus, a print zone 722 is defined adjacent to nozzles 716 in an area between printhead assembly 702 and print media 718. In one example, printhead assembly 702 is a scanning type printhead assembly. As such, mounting assembly 706 includes a carriage for moving printhead assembly 702 relative to media transport assembly 708 to scan print media 718. In another example, printhead assembly 702 is a non-scanning type printhead assembly. As such, mounting assembly 706 fixes printhead assembly 702 at a prescribed position relative to media transport assembly 708. Thus, media transport assembly 708 positions print media 718 relative to printhead assembly 702.

Electronic controller 710 typically includes a processor, firmware, software, memory components including volatile and non-volatile memory components, and other printer electronics for communicating with and controlling printhead assembly 702, mounting assembly 706, and media transport assembly 708. Electronic controller 710 receives data 724 from a host system, such as a computer, and temporarily stores data 724 in a memory. Typically, data 724 is sent to inkjet printing system 700 along an electronic, infrared, optical, or other information transfer path. Data 724 represents, for example, a document and/or file to be printed. As such, data 724 forms a print job for inkjet printing system 700 and includes print job commands and/or command parameters.

In one example, electronic controller 710 controls printhead assembly 702 for ejection of fluid drops from nozzles 716. Thus, electronic controller 710 defines a pattern of ejected fluid drops which form characters, symbols, and/or other graphics or images on print media 718. The pattern of ejected fluid drops is determined by the print job commands and/or command parameters.

Printhead assembly 702 includes one (i.e., a single) printhead die 714 or more than one (i.e., multiple) printhead die 714. In one example, printhead assembly 702 is a wide-array or multi-head printhead assembly. In one implementation of a wide-array assembly, printhead assembly 702 includes a carrier that carries a plurality of printhead dies 714, provides electrical communication between printhead dies 714 and electronic controller 710, and provides fluidic communication between printhead dies 714 and fluid supply assembly 704.

In one example, inkjet printing system 700 is a drop-on-demand thermal inkjet printing system wherein printhead assembly 702 includes a thermal inkjet (TIJ) printhead that implements a thermal resistor as a drop ejecting element to vaporize fluid in a fluid chamber and create bubbles that force fluid drops out of nozzles 716. In another example, inkjet printing system 700 is a drop-on-demand piezoelectric inkjet printing system wherein printhead assembly 702 includes a piezoelectric inkjet (PIJ) printhead that implements a piezoelectric actuator as a drop ejecting element to generate pressure pulses that force fluid drops out of nozzles 716.

Although specific examples have been illustrated and described herein, it will be appreciated by those of ordinary skill in the art that a variety of alternate and/or equivalent implementations may be substituted for the specific examples shown and described without departing from the scope of the present disclosure. This application is intended to cover any adaptations or variations of the specific examples discussed herein. 

1. A media transport assembly, comprising: a feed roller to be rotated in a first direction; and an input/output roller to be rotated in the first direction to direct media into a media path with rotation of the feed roller in the first direction, the feed roller to be rotated in a second direction opposite the first direction to advance the media within the media path, and with the rotation of the feed roller in the second direction, the input/output roller to be temporarily decoupled from rotation with the feed roller.
 2. The media transport assembly of claim 1, with the input/output roller temporarily decoupled from the rotation with the feed roller, a trailing portion of the media to be supported by the input/output roller.
 3. The media transport assembly of claim 1, with the input/output roller temporarily decoupled from the rotation with the feed roller, a leading portion of the media to be advanced in the second direction with the feed roller.
 4. The media transport assembly of claim 1, with further rotation of the feed roller in the second direction, the input/output roller to be rotated in the second direction with rotation of the feed roller in the second direction.
 5. The media transport assembly of claim 1, further comprising: a transmission to transfer rotational power to the feed roller and the input/output roller, the transmission including a delay clutch to temporarily decouple the rotation of the input/output roller from the rotation with the feed roller.
 6. A media transport assembly, comprising: a media path to route media to a print zone; an input/output roller at an end of the media path to direct media into and out of the media path; a feed roller to advance media within the media path; and a transmission to rotate the input/output roller with rotation of the feed roller, the transmission including a delay clutch to temporarily decouple rotation of the input/output roller from rotation of the feed roller based on a direction of rotation of the feed roller.
 7. The media transport assembly of claim 6, wherein the transmission is to rotate the input/output roller in a first direction with rotation of the feed roller in the first direction, and rotate the input/output roller in a second direction opposite the first direction with rotation of the feed roller in the second direction after a delay of the delay clutch.
 8. The media transport assembly of claim 6, wherein, with the input/output roller temporarily decoupled from rotation of the feed roller, a trailing portion of the media is to be at the input/output roller, the input/output roller is free to rotate in a first direction, and a leading portion of the media is to be advanced by the feed roller in a second direction opposite the first direction.
 9. The media transport assembly of claim 6, wherein the delay clutch includes a first delay gear, a second delay gear, and a delay disc interposed between the first delay gear and the second delay gear, the delay disc to temporarily decouple rotation of the second delay gear from rotation of the first delay gear based on a direction and amount of rotation of the first delay gear, wherein the transmission includes a first drive gear to drive the feed roller and the first delay gear, and a second drive gear to be driven by the second delay gear and drive the input/output roller.
 10. A media transport method, comprising: rotating a feed roller in a first direction; coupling rotation of an input/output roller with the rotating the feed roller in the first direction to direct media into a media path; and rotating the feed roller in a second direction opposite the first direction to advance the media within the media path, including temporarily decoupling rotation of the input/output roller from the rotating with the feed roller.
 11. The method of claim 10, further comprising: further rotating the feed roller in the second direction opposite the first direction to further advance the media within the media path, including re-coupling rotation of the input/output roller with the rotating of the feed roller.
 12. The method of claim 10, further comprising: supporting a trailing portion of the media at the input/output roller during the temporarily decoupling of rotation of the input/output roller.
 13. The method of claim 10, further comprising: advancing a leading portion of the media in the second direction with the feed roller during the temporarily decoupling of rotation of the input/output roller.
 14. The method of claim 10, wherein temporarily decoupling rotation of the input/output roller from the rotating with the feed roller includes temporarily decoupling rotation of the input/output roller from the rotating of the feed roller with a delay clutch in a power transmission path between a first gear driving the feed roller and a second gear driving the input/output roller.
 15. The method of claim 14, wherein temporarily decoupling rotation of the input/output roller from the rotating with the feed roller with the delay clutch includes temporarily decoupling rotation of a second delay gear from rotation of a first delay gear with a delay disc interposed between the first delay gear and the second delay gear. 